Promoter nucleosome dynamics regulated by signaling through the CTD code
- University of Namur, Belgium
- LSU Health Sciences Center, United States
- Universidad de Salamanca, Spain
- Universitat Pompeu Fabra, Spain
Abstract
The phosphorylation of the RNA polymerase II CTD plays a key role in delineating transcribed regions within chromatin by recruiting histone methylases and deacetylases. Using genome-wide nucleosome mapping, we show that CTD S2 phosphorylation controls nucleosome dynamics in the promoter of a subset of 324 genes, including the regulators of cell differentiation ste11 and metabolic adaptation inv1. Mechanistic studies on these genes indicate that during gene activation a local increase of phosphoS2 CTD nearby the promoter impairs the phosphoS5 CTD dependent recruitment of Set1 and the subsequent recruitment of specific HDACs, which leads to nucleosome depletion and efficient transcription. The early increase of phosphoS2 results from the phosphorylation of the CTD S2 kinase Lsk1 by MAP kinase in response to cellular signaling. The artificial tethering of the Lsk1 kinase at the ste11 promoter is sufficient to activate transcription. Therefore, signaling through the CTD code regulates promoter nucleosomes dynamics.
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© 2015, Materne et al.
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Promoter nucleosome dynamics regulated by signaling through the CTD code
eLife 4:e09008.
https://doi.org/10.7554/eLife.09008
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